为什么我的函数返回"newLine.unshift(startN) is not a function"

Question

我一直试图编写一个递归函数来获取一系列数字，但我遇到了一个错误，说'newLine. unshift(startN) is not a function'。

以下是代码：

function rangeOfNumbers(startN, endN) {
if (startN - endN === 0) {
return "The starting number will always be less than or equal to the ending number";
} else {
const newLine = rangeOfNumbers(startN + 1, endN);
newLine.unshift(startN);
return newLine;
}
}
console.log(rangeOfNumbers(1, 7));

有人能帮我找出提到错误的原因吗？

Answer 1

rangeOfNumbers(1，7(/newLine=rangeOfNumber(2，7(
rangeOfNumbers
rangeOfNumbers(7，7(/newLine="；起始数字将始终为">

typeofnewLine=字符串
newLine.unshift((>gt；undefined/unshift不可用JS字符串